#include <bits/stdc++.h>
using namespace std;
#define int long long
signed main(){
  int N;
  cin>>N;
  if(N >= 16){
      cout<<65535<<endl;
      return 0;
      
  }
  vector<vector<int>> dp(N+1,vector<int>(70000));
  dp[0][0] = 1;
  vector<int> S(N);
  for(int i=0;i<N;i++) cin>>S[i];
  for(int i=0;i<N;i++)for(int j=0;j<69990;j++){
      if(!dp[i][j]) continue;
      for(int k=0;k<16;k++){
          dp[i+1][j|S[i]] = 1;
          S[i] = S[i]/2+(1<<15)*(S[i]%2);
      }
  }
  for(int i=68000;i>=0;i--)if(dp[N][i]){
      cout<<i<<endl;
      return 0;
  }
}